Vehicle operators frequently need to operate their vehicles in unfamiliar locations and/or in conditions of poor visibility. It is postulated that such unfamiliarity and poor visibility may disorient a vehicle operator and/or hamper the vehicle operator's ability to navigate the vehicle. For example, a pilot of an aircraft taxiing through an airport environment that is either unfamiliar to the pilot, or that is obscured by weather conditions, or both, may require some assistance in ascertaining the aircraft's orientation with respect to the terrain, including ramps, taxiways and runways, around the aircraft.
To address this issue, some systems have been devised to provide a vehicle operator with a three-dimensional display that graphically depicts the actual terrain (including runways, taxiways and ramps) around the vehicle. To further assist the vehicle operator, such systems also include a compass in the display that shows the vehicle's heading. However, such systems provide only a two-dimensional compass card overlaying the image of the environment. It is believed that vehicle operators may find it difficult to assimilate and utilize heading information provided by a two-dimensional compass card displayed in the midst of a three-dimensional display. For example, it is thought that a pilot may have difficulty correlating a compass heading depicted on the two-dimensional compass card with a route depicted three-dimensionally on a display screen. Additionally, some existing displays do not include a graphic indication of the location of the vehicle with respect to the depicted terrain. The present disclosure addresses these and other problems.